The problem: During MRI procedures, delivering audio has been cumbersome due to sloppy headphone-to-patient interface provided by conventional headband-type earphones. This conventional device also introduces more foreign objects into the imaging cavity and also increases the distance between the patient and the imaging surface. This reduces the efficiency of the images and increases patient discomfort. These problems are further worsened when performing MRI scans on children. Children typically tend to move around more than adult subjects during scans. Therefore, it is important to deliver sound to occupy the child patient being scanned. It is important to have a large degree of adjustability to accommodate the various ranges of patient ear locations. Movement is also an issue and it is important to restrain the patient's head movements as much as possible without fully restricting an emergency evacuation of the patient from the MRI system.
U.S. Pat. No. 8,854,042, titled “METHOD AND COILS FOR HUMAN WHOLE-BODY IMAGING AT 7 T,” filed 5 Aug. 2011 and issued 9 Feb. 2012 to John Thomas Vaughan, Jr. and Charles A. Lemaire, is incorporated herein by reference. U.S. Pat. No. 8,854,042 describes MRI coils for human whole-body MR imaging. A progressive series of five new coils is described. The first coil solves problems of transmit-field inefficiency and inhomogeneity for heart and body imaging, with a close-fitting, 16-channel TEM conformal array design with efficient shield-capacitance decoupling. The second coil progresses directly from the first with automatic tuning and matching, an innovation of huge importance for multi-channel transmit coils. The third coil combines the second, auto-tuned multichannel transmitter with a 32-channel receiver for best transmit-efficiency, control, receive sensitivity and parallel-imaging performance. The final two coils extend the innovative technology of the first three coils to multi-nuclear (31P—1H) designs to make practical human-cardiac imaging and spectroscopy possible for the first time at 7 T.
U.S. Pat. No. 8,604,791, titled “ACTIVE TRANSMIT ELEMENTS FOR MRI COILS AND OTHER ANTENNA DEVICES,” filed 9 Sep. 2010 and issued 10 Dec. 2013 to John Thomas Vaughan, Jr and Charles A. Lemaire, is incorporated herein by reference. This application describes apparatus and method that include amplifiers for transceiver antenna elements, and more specifically to power amplifying an RF (radio frequency) signal using a distributed power amplifier having electronic devices (such as field-effect transistors) that are thermally and/or mechanically connected to each one of a plurality of antenna elements (also called coil elements) to form a hybrid coil-amplifier (e.g., for use in a magnetic-resonance (MR) imaging or spectroscopy machine), and that is optionally adjusted from a remote location, optionally including remotely adjusting its gains, electrical resistances, inductances, and/or capacitances (which controls the magnitude, phase, frequency, spatial profile, and temporal profile of the RF signal)—and, in some embodiments, the components are compatible with, and function in, high fields (such as a magnetic field of up to and exceeding one tesla or even ten tesla or more and/or an electric field of many thousands of volts per meter).
U.S. Patent Application Publication US 2012/0223709 titled “SIMULTANEOUS TX-RX FOR MRI SYSTEMS AND OTHER ANTENNA DEVICES,” of U.S. patent application Ser. No. 13/407,751 filed 28 Feb. 2012 by Scott M. Schillak, John Thomas Vaughan, Jr., Charles A. Lemaire and Matthew T. Waks, is incorporated herein by reference. This application describes an apparatus and a method that are more efficient and flexible, and obtain and connect high-power RF transmit signals (TX) to RF-coil devices in an MR machine or other devices and simultaneously receive signals (RX) and separate net receive signals NRX) of interest by subtracting or filtering to remove the subtractable portion of the transmit signal (STX) from the RX and preamplifying the NRX and signal processing the preamplified NRX. In some embodiments, signal processing further removes artifacts of the transmitted signal, e.g., by digitizing the NRX signal, storing the digitized NRX signal in a memory, and performing digital signal processing. In some embodiments, the present invention also includes pre-distorting the TX signals in order to be better able to identify and/or remove the remaining artifacts of the transmitted signal from the NRX signal. This solution also applies to other high-power RF-transmit-antennae signals.
Patent application Ser. No. 13/831,752 titled “SNAP-ON COAXIAL CABLE BALUN AND METHOD FOR TRAPPING RF CURRENT ON OUTSIDE SHIELD OF COAX AFTER INSTALLATION,” filed 15 Mar. 2013 by Matthew T. Waks, Scott M. Schillak and Charles A. Lemaire (which issued as U.S. Pat. No. 9,160,295 on Oct. 13, 2015), is incorporated herein by reference. This application describes an apparatus and a method for a radially attachable RF trap attached from a side to a shielded RF cable. In some embodiments, the RF trap creates a high impedance on the outer shield of the RF cable at a frequency of RF signals carried on at least one inner conductor of the cable. In some embodiments, an RF-trap apparatus for blocking stray signals on a shielded RF cable that has a peripheral shield conductor and a inner conductor for carrying RF signals includes: a case; an LC circuit having a resonance frequency equal to RF signals carried on the inner conductor; projections that pierce and connect the LC circuit to the shield conductor; and an attachment device that holds the case to the cable with the LC circuit electrically connected to the shield conductor of the shielded RF cable.
U.S. Pat. No. 8,299,681 issued to Snyder, et al. on Oct. 30, 2012, titled “Remotely adjustable reactive and resistive electrical elements and method,” and is incorporated herein by reference. U.S. Pat. No. 8,299,681 describes an apparatus and method that include providing a variable-parameter electrical component in a high-field environment and based on an electrical signal, automatically moving a movable portion of the electrical component in relation to another portion of the electrical component to vary at least one of its parameters. In some embodiments, the moving uses a mechanical movement device (e.g., a linear positioner, rotary motor, or pump). In some embodiments of the method, the electrical component has a variable inductance, capacitance, and/or resistance. Some embodiments include using a computer that controls the moving of the movable portion of the electrical component in order to vary an electrical parameter of the electrical component. Some embodiments include using a feedback signal to provide feedback control in order to adjust and/or maintain the electrical parameter. Some embodiments include a non-magnetic positioner connected to an electrical component configured to have its RLC parameters varied by the positioner.
U.S. Pat. No. 5,449,206 to Lockwood issued Sep. 12, 1995 titled “Ball and socket joint with internal stop” and is incorporated herein by reference. U.S. Pat. No. 6,042,155 to Lockwood issued Mar. 28, 2000 titled “Ball and socket joint with internal stop” and is incorporated herein by reference. These patents describe a first connector includes opposite ball and socket elements having a passageway formed therethrough. The socket element has a cavity formed therein for receiving a ball element of a second hose connector to form a hose assembly. A ring is disposed within the cavity for limiting pivotal movement of a ball element inserted therein to minimize the risk that the connectors, and thereby the hose assembly, will separate.
There is a long-felt need for a method and apparatus for adjustable audio delivery and head restraint in an MRI system.